Mold and method for forming monoliths



R. F. GRADY.

MOLD A ND METHOD FOR FOHMING MoNomHs.-

' APPLICATION FILED JUNE l, 1920.y

1,4172599. Patented May 3o, 1922.

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narran stares ROBERT rf. GRADY, or sr. Louis Mrssonar.

MOLD ann METHOD rois roRMrNG MoNoLIrHs.

Specification of Letters Patent. ,Patted Bray 3() 'Applicationfledlune 1, 1920. `Serial No. 385,61*?.r f ,A

To all @U3/wm t may concerny Be it known that I, ROBERT vF. GRADY, a citizen of the United States, residingat the city of St. Louis and State of Missouri, h ave invented a. new and useful lifold'and Method for Forming Monoliths, ofi which the fol.v

lowing is a specification.v

hereinafter set'forth. y An obj ect of they invention is to provide a mold and the method7 of utilizing' the same,

whereby monolithicstructures may be made and duplicated-from one mold7 V.with provision for forming upon the structure eitherV raisedor incised letters, numerals, characters or designs. Y

Another object of the invention is to provide a mold and the method of using the same to form a monolithic structure having selected letters, numerals, characters and designs on a face or faces thereof,iWith provision whereby the letter, numeral, character or design-forming matrices Will move in conformity with the contraction or movement of the body 'of the structure during` the course of the formation thereof in the mold.

Additional advantages ofthe mold and the method Will be apparent from thefollowing detailed description of the invention taken in connection With the accompanying drawing, infvvhich- Fig. l is a perspective view-of the mold showing one Wall thereof removed.

Fig. 2 is a cross section through the mold.

Fig. 3 is a structure formed in the mold by the practice of the invention For the purpose of illustration the form of mold selected is one for forming a monolith suitable for a head stone, although it Will be understood that the invention may be utilized for forming various monoliths of any desired contour.

The mold structure is formed from slabs preferably composed of plaster of Paris, or

other suitable material may be employed, and comprises end Walls l, a front Wall 2, a rear Wall 3 and a top 4c. The matching edges of the members of the moldbeing arranged to fit closely together, and lin order that the various members of the mold may be assembled vvith facility' and properly centered, suitable knobs 5 are formed on one of the matching faces and registering recesses 6V are formed on the other of the matching faces. One or4 more of they Walls may be formed yWith a recess 7. in its inner face* which is adapted torecelve the matrices for forming the letters, numerals, characters. or demera-1,l characterr or design recessed in the thereof, as may be desired.

yface thereof or rising in relief from the faceorvdesigns onthe structure Will bein relief and, conversely, when the letters, nu rnergals,`

signs upon the face ofthe structure formed by the mold. Thesey matrices are preferably e 1n thesform of blocks '8 having a` letternu This .invention relates to a. mold andl method for forming monoliths, and consists, in thek novel constructionV andv procedure characters-ory designs are in'. relief on the `blocks 18 they' will ,form incised letters, l numerals, characters ordesigns in the structure. `c

The mold is prepared for forming the various inscriptions before it is assembled by properly arranging the block-carrying matrices in alinement and at proper intervals in the recess or recesses?. The 7space betvveenthe blocksI is lled in with plastic clay, or other suitable material and the area of the recess not occupied by the blocks `is filled in with the same material. This material serves to hold the blocks in theirv proper adjustment and to present a smoothmoldingy surface throughout the area of the Fece/SS.

In practice the inner surface of the-moldA elements are then covered with plastic clay or similar material, and the same is packed closely against the surface.l The mold is then yassembled and further packed With plastic clay, or other suitable material as 1 y may be used in forming the structure. .l

After the mold has been filled the elements of the mold are secured together and the structure allowed to dry. During the "drying process there Will be a slight shrinkage of the material but, inasmuchas the blocks containing the different characters are set up in the same material, there Will be shrinkage thereof substantially uniform with the shrinkage of the material lof the structure. In other Words, the character-forming matrices will move in substantial uniformity p with the contraction of the surface `of the structure upon which the characters are formed. After the structure has driedy suf`l fciently to become set, the mold elements arel released and removed from the structure. The structure may then be treated and baked.,

Obviously7 from the foregoing it will be understood that by the mold and method of this invention any desired characters may be formed in integral union With the body of the structure and that the characters thiis formed Will be Sharp in outline and Will retain the original alinement conforming to the arrangement thereof in preparation of the mold when the block-carrying matrices are set up in the recesses.

Various modifications may be made Withoiit departing from the spirit and scope of the invention. Vhat I claim Vand desire to secure by Letters Patent, is

l. "In a moid of the class described7 the' combination of one side of the mold, matrices disposed' on the inner face of said mold,

a plastic composition surrounding the matrices and securing them to I the Wall, said composition possessing` approximately the same shrinking qualities as the article forming material whereby the matrices Willbe .permitted vto shift position as the vmaterial shrinks. t

2. In a'mold of the class described7 the combination of one side of the mold `having by the matrices Will be permitted to shift position as said material shrinks.

3. A method of casting` a monolithic striicture and forming an imprint .thereon consisting in holding a matrix in a mold,`by a plastic composition around the matrixiand placing the structure forming plastic in the mold before hardening of said first' mentioned plastic composition.

4L. A mold, including` a Wall havinga -recess in the inner face thereof, solid blocks carrying character-forming matrices, and

yieldable material for filling saidv recess and holding saidl blocks yWithin said recess'.y

The method of 'forming Vacmonolith,L

W-hichconsists in setting` matrices in ayieldable material in a recess of a Wallv of the mold, packing plastic material against said mold Wall, and allowingsaidrmaterial to set.

in said mold. i*

ROBERT F.' vGERADY, 

